diff --git a/forge-game/src/main/java/forge/game/ForgeScript.java b/forge-game/src/main/java/forge/game/ForgeScript.java
index 7863f76d321..277476cc742 100644
--- a/forge-game/src/main/java/forge/game/ForgeScript.java
+++ b/forge-game/src/main/java/forge/game/ForgeScript.java
@@ -188,7 +188,7 @@ public class ForgeScript {
         } else if (property.startsWith("XCost")) {
             String comparator = property.substring(5, 7);
             int y = AbilityUtils.calculateAmount(sa.getHostCard(), property.substring(7), sa);
-            return Expressions.compare(sa.getXManaCostPaid(), comparator, y);
+            return Expressions.compare(sa.getXManaCostPaid() == null ? 0 : sa.getXManaCostPaid(), comparator, y);
         } else if (property.equals("hasTapCost")) {
             Cost cost = sa.getPayCosts();
             return cost != null && cost.hasTapCost();